The invention relates to a process and a plant for preparation of one or more reaction products, especially dimethyl ether or other oxygenates, in which a first methane-rich feed stream is subjected to a partial oxidation process and/or an autothermal reforming process and a second methane-rich feed stream is subjected to a steam reforming process, and in which a first synthesis gas-containing output stream is formed by means of the partial oxidation process and/or the autothermal reforming process and a second synthesis gas-containing output stream is formed by means of the steam reforming process, where synthesis gas from the first output stream and synthesis gas from the second output stream are used to form a collective synthesis gas stream and fluid from the collective synthesis gas stream is subjected to a molecular weight-increasing reaction in a synthesis feed stream to obtain a synthesis output stream comprising carbon dioxide and the reaction product(s), characterized in that at least one carbon dioxide-rich first recycle stream is formed from fluid from the synthesis output stream, and in that fluid from the first recycle stream is subjected to the steam reforming process.